β-内酰胺酶抑制肽的活性研究

目的 通过合成和筛选具有一定抑酶作用的β-内酰胺酶抑制肽,考察其抑制活性及抑制动力学生化特征,以用于产β-内酰胺酶耐药菌所致感染的临床治疗。方法 固相合成法在计算机上三维模拟设计合成β-内酰胺酶抑制肽。选取我院08年临床分离鉴定的产酶菌8株,测定临床常用抗生素对8株细菌的MIC值,采用试管稀释法进行β-内酰胺酶抑制肽活性初步筛选。分光光度法研究抑制肽对8株产酶菌所产β-内酰胺酶的抑酶效力,Dixon作图法求取抑制常数Ki,计算相关抑制动力学参数。结果 合成了6段系列短肽分子,筛选得到3段具有抑制活性的抑制肽,抑制底物动力学研究验证3段β-内酰胺酶抑制肽具有一定抑制活性,但抑制常数均较大,其抑制方式均为竞争性抑制。结论     

向日葵胰蛋白酶抑制剂SFTI的合成及酶抑制动力学研究

目的 考察合成的向日葵胰蛋白酶抑制剂的抑制效果,计算其抑制常数Ki.方法 采用Fmoc固相化学合成方法,反相柱纯化后用CytofluorTM微孔板发光检测仪测定向日葵胰蛋白酶抑制剂的抑制常数.结果与结论 向日葵胰蛋白酶抑制剂的Ki值为2.2nM±0.5(n=8),抑制效果良好.     

血管紧张肽转换酶抑制药在冠心病治疗中的应用

血管紧张肽转换酶抑制药可通过改善心肌供氧耗氧平衡、改善血管内皮功能、抑制交感神经兴奋性、抑制血管平滑肌迁移和增殖、抑制血小板聚集和促进纤维蛋白溶解、抑制低密度脂蛋白氧化修饰、抑制心肌肥厚、延迟心脏重构等机制在动脉粥样硬化和冠心病的治疗中发挥重要作用     

抗肿瘤新药血管内皮抑制素的研究进展

血管内皮抑制素能特异地抑制血管内皮细胞增殖和迁移,抑制新生血管形成,切断肿瘤生长所需的营养途径,从而有效抑制肿瘤的生长和转移,是目前发现的最为理想的血管形成抑制因子,为肿瘤的治疗提供了新途径。本文对血管内皮抑制素的研究进展作一浅述。     

胆碱酯酶抑制药治疗阿尔茨海默病

阿尔茨海默病患者胆碱能受体功能低下,导致认知障碍,胆碱酯酶抑制药通过抑制胆碱酯酶,抑制乙酰胆碱降解,改善认知功能,但也可伴拟胆碱能不良反应（如恶心、呕吐和腹泻）。非那西汀抑制1A2酶,抑制石杉碱甲代谢70%。     

引流熊胆的抗炎免疫抑制作用

引流熊胆Ｉｇ能明显地抑制二甲苯、巴豆油所致小鼠耳壳肿胀．抑制小鼠腹腔毛细血管通透性．抑制角叉菜胶所致大鼠足肿胀及Ｐｒｅｕｎｄ完全性剂所致大鼠关节炎；对肾上腺、胸腺、脾脏及淋巴结重量无明显影响。抑制小鼠棉球肉芽肿增生，抑制小鼠单核巨噬细胞吞噬功能。表明引流熊胆具有抑制急、慢性及免疫性炎症作用和免疫抑制作用。引流熊胆还抑制大鼠热烫足肿胀．减少大鼠炎症部位ＰＧＥ２含量。提示引流熊胆的抗炎作用与抑制炎症部位的激肽类和ＰＧＥ２的合成与释放有关。     

内皮抑制素通过抑制基质金属蛋白酶-2而抑制血管新生(英文)

目的　研究内皮抑制素抑制血管新生作用的机制。方法　用碱性成纤维细胞生长因子 (bFGF)处理体外原代培养人脐静脉内皮细胞 ;用三维胶原模型研究bFGF诱导的血管新生作用 ;用明胶电泳和蛋白印迹法研究分泌于培养基中的基质金属蛋白酶的活性和含量 ;RT PCR法研究基质金属蛋白酶的mRNA水平。结果　内皮抑制素显著抑制bFGF诱导的内皮细胞血管新生能力 ;抑制内皮细胞分泌的基质金属蛋白酶 2的表达及其mRNA的水平。结论　内皮抑制素通过抑制基质金属蛋白酶 2的表达而抑制血管新生     

Survivin p16在乳腺癌组织中的表达和临床意义

<正>Survivin基因是一种凋亡抑制基因,是凋亡蛋白抑制因子(inhibitor of apoptosis protein,IAP)的家族成员,具有抑制凋亡和参与细胞周期调控的双重功能。P16是肿瘤抑制因子。     

抑制血小板聚集药物的抵抗

血小板激活在急性冠脉综合征的发生中起重要的作用。抑制血小板聚集药物治疗可以抑制血小板的粘附、聚集和释放功能，从而抑制血栓形成。然而，抑制血小板聚集药物的作用个体差异很大。有的患者对抑制血小板聚集药物存在抵抗现象，尽管长期服用常规剂量的药物，但仍发生血栓栓塞事件或实验室检测发现其血小板聚集能力不能被很好地抑制，未能达到预期的疗效。本文对常用抑制血小板聚集药物对阿司匹林和氯毗格雷抵抗作一综述。[第一段]     

重组人可溶性血管内皮细胞

血管内皮细胞生长抑制因子（Vascular Endothelial GrowthInhibitor,VEGI）是从人脐静脉内皮细胞（HUVEC）cDNA文库筛选到的一个TNF超家族新成员。为研究重组可溶性人VEGI对新生血管形成抑制活性,检测了重组可溶性人VEGI对建株人脐静脉内皮细胞（ECV304）增殖抑制活性以及对兔角膜诱生血管、鸡胚尿囊膜（CAM）血管的抑制活性。表明可溶性人VEGI可以直接抑制ECV304内皮细胞的增殖,抑制兔角膜诱生血管、CAM血管形成。VEGI是一种新的血管内皮细胞生长抑制因子,强烈抑制新生血管形成,有望应用于肿瘤的治疗。     

In vivo antimalarial activity of ginseng extracts

Context: Novel antimalarial agents are in demand due to the emergence of multidrug resistant strains. Ginseng, a medicinal plant with antiparasitic activity, contains components that can be used to treat the tropical disease malaria.

Objective: Ginsenosides and polysaccharides are active components of ginseng. This study aimed to elucidate the ability of these compounds to inhibit the replication of Plasmodium yoelii in an attempt to determine whether the medicinal uses of ginseng are supported by pharmacological effects. New antimalarial compounds may be developed from ginsenosides and water-soluble ginseng polysaccharides (WGP).

Materials and methods: Ginsenosides and ginseng polysaccharides were prepared from ginseng. Antimalarial activities were examined by 4-day tests and repository tests. Macrophage phagocytosis was tested in normal and malaria-bearing mice.

Results: Ginseng polysaccharides could inhibit residual malaria infection. After a 6-day treatment, the parasitemia reductions of WGP and acidic ginseng polysaccharide (WGPA) were 55.66% and 64.73% at 200?mg/kg/day, respectively. Ginsenosides showed significant antimalarial activity on early infection. Protopanaxadiol-type ginsenosides caused 70.97% chemosuppression at 50?mg/kg/day, higher than 52.8% of total ginsenosides at the same dose.

Discussion and conclusion: Protopanaxadiol-type ginsenosides have remarkably suppressive activity during early infection, while acidic ginseng polysaccharides have significant prophylactic activity against malaria by stimulating the immune system. We propose that the activity of ginsenosides is dependent upon non-specific carbohydrate interactions and that the activity of ginseng polysaccharides is due to immunological modulation. Ginsenosides and ginseng polysaccharides might have a potential application in antimalarial treatments.     

昆布多糖对肾纤维化大鼠肾组织内质网应激的保护作用

目的研究昆布多糖对肾纤维化大鼠肾组织内质网应激(ERS)分子伴侣GRP78、GRP94蛋白表达的影响。方法采用单侧输尿管梗阻(UUO)诱导大鼠肾间质纤维化的动物模型,将大鼠随机分为假手术组、模型组、依那普利组、昆布多糖高、中、低剂量组。术后第7天处死大鼠,收集血清测定肌酐(Scr)、尿素氮(BUN)水平。采用Western免疫印迹法检测大鼠肾组织GRP78、GRP94的蛋白表达;采用HE、Masson染色检测肾小管损伤及肾间质纤维化程度。结果各治疗组与模型组比较大鼠肾小管间质损伤指数、肾间质纤维化程度、血清Scr、BUN水平及肾组织GRP78、GRP94蛋白表达有差异(P<0.05;P<0.01),昆布多糖与依那普利组比较,大鼠肾组织GRP78、GRP94表达升高(P<0.05),肾小管间质损伤及肾间质纤维化程度明显降低(P<0.05),肾功能Scr、BUN明显降低(P<0.05)。结论UUO早期昆布多糖可能通过上调ERS分子伴侣GRP78、GRP94蛋白表达,协助变性蛋白进行重新折叠、装配及跨膜转运,抑制未折叠蛋白反应,阻断ERS应激信号传导通路,从而减轻肾间质纤维化的发生和发展。     

Comparisons between white ginseng radix and rootlet for antidiabetic activity and mechanism in KKAy mice

The mechanisms responsible for the antidiabetic activity of both the white ginseng radix (Ginseng Radix Alba, GRA) and the rootlet (Ginseng Radix Palva, GRP) were investigated. After a four week oral administration, the fasting blood glucose levels in the GRA- and GRP-treated groups were lower when compared to the control group. To elucidate the hypoglycemic mechanism(s) of the ginseng radices, glucose absorption from the small intestine, hepatic hexokinase and glucose-6-phosphatase activities, in addition to PPAR-gamma expression in adipose tissue were examined. The results strongly suggest that GRA can improve hyperglycemia in KKAy mice, possibly by blocking intestinal glucose absorption and inhibiting hepatic glucose-6-phosphatase, and GRP through the upregulation of adipocytic PPAR-y protein expression as well as inhibiting intestinal glucose absorption.     

人参有效成分抗疲劳作用机制的研究进展

人参不仅是我国传统珍贵的中药材，更是食疗保健佳品，具有多方面抗疲劳作用。人参抗疲劳的主要活性成分包括人参多糖、寡肽和皂苷，可能通过调节糖类代谢、激活磷脂酰肌醇-3-羟激酶（PI3K）/蛋白激酶B（Akt）/哺乳动物雷帕霉素靶蛋白（mTOR）等信号通路、提高骨骼肌线粒体供能效力和加快自由基清除从而产生抗疲劳作用。综述人参多糖、蛋白质、人参皂苷类有效成分抗疲劳药理作用机制，旨在为人参用于各类抗疲劳功能产品的开发应用提供依据。     

The inhibitory effect of ginseng pectin on L-929 cell migration

We tested the effects of ginseng pectin prepared by enzymatic hydrolysis of ginseng polysaccharides on cell migration. Ginseng pectin impaired the migration of L-929 cells and reduced their migration speed by up to 50% of control in the presence or absence of serum, suggesting it worked on both serum-dependent and serum-independent migration pathways. Ginseng pectin impaired cell migration via decreased cell spreading. These findings represent a significant contribution towards understanding the bioactivities of ginseng polysaccharides and applying them to health food and medicine.     

Inhibition of Helicobacter pylori adhesion to human gastric adenocarcinoma epithelial cells by acidic polysaccharides from Artemisia capillaris and Panax ginseng

Helicobacter pylori specifically adheres to host cells, mainly based on carbohydrate-mediated cell-cell interactions. Previously, we investigated the anti-adhesive effect of polysaccharide fractions from Artemisia capillaris and Panax ginseng, using hemagglutination and enzyme-linked glycosorbent assays. In the present study, each active polysaccharide fraction was further purified, resulting in a single peak (fraction F2) using gel filtration FPLC, in which no protein content was detectable. Using scanning electron microscopy, we examined the inhibitory effects of these polysaccharides on the attachment of H. pylori to the human gastric adenocarcinoma epithelial cell line. The bacterial attachment to the cell line was inhibited by these polysaccharides in the range of the concentrations studied (0.2 - 2.8 mg/mL), showing their minimum inhibitory concentration at as low as 0.2 mg/mL. The bacterial binding was inhibited more effectively by P. ginseng polysaccharides, than by those from A. capillaris. The purified polysaccharides contain similar sugar compositions and have high amounts of uronic acids. Our results suggest that acidic carbohydrates may play an important role in the inhibitory activity on H. pylori adhesion to host cells and that our established purification protocol can be applied to obtain active acidic polysaccharides from plant sources.     

四种多糖抗溃疡作用的研究

糊精、人参果胶、肝素和硫酸软骨素A对四种大鼠实验性胃溃疡(消炎痛型、应激型、幽门结扎型及醋酸型)均有不同程度的抑制作用,前两种植物多糖抗溃疡作用比后两种酸性粘多糖强。其中以糊精的抗溃疡作用最显著。多糖的抗溃疡作用可能与其降低胃酸和抑制胃蛋白酶活性有关。     

Botanical characteristics, pharmacological effects and medicinal components of Korean Panax ginseng C A Meyer

Korean Panax ginseng C A Meyer is mainly used to maintain the homeostasis of the body, and the pharmacological efficacy of Korean ginseng identified by modern science includes improved brain function, pain-relieving effects, preventive effects against tumors as well as anti-tumor activity, enhanced immune system function, anti-diabetic effects, enhanced liver function, adjusted blood pressure, anti-fatigue and anti-stress effects, improved climacteric disorder and sexual functions, as well as anti-oxidative and anti-aging effects. Further clinical studies of these pharmacological efficacies will continue to be carried out. Korean ginseng is found to have such main properties as ginsenoside, ployacetylene, acid polysaccharide, anti-oxidative aromatic compound, and insulin-like acid peptides. The number of ginsenoside types contained in Korean ginseng (38 ginsenosides) is substantially more than that of ginsenoside types contained in American ginseng (19 ginsenosides). Furthermore, Korean ginseng has been identified to contain more main non-saponin compounds, phenol compounds, acid polysaccharides and polyethylene compounds than American ginseng and Sanchi ginseng.     

枇杷花的研究进展及其药效评价思路的探讨

枇杷花具有重要的药用价值和开发潜力.近年来国内外相关研究主要集中在枇杷花的化学成分、提取和精制工艺、药理效应和应用开发等方面,但存在有效性评价方法不系统和有效剂量不明确等问题.在综述枇杷花化学成分、提取和精制工艺、药理作用的基础上,提出如下研究思路:基于传统用药经验,应用经典、快速的动物模型确定有效剂量范围,整合多致病...     

人参细胞培养物中水溶性多糖的研究

人参细胞培养物中水溶性多糖经提取后,用果胶酶和Sevag法除去其中蛋白,用Sephadex G-100柱进行分离、纯化得到DPSCG1和DPSCG2两个洗脱峰。经醋酸纤维素薄膜电泳和琼脂糖凝胶电泳,证明DPSCG1和DPSCG2均为均一性多糖,两者经水解和薄层层析结果均由鼠李糖、木糖、阿拉伯糖、半乳糖和半乳糖醛酸等组成,经Sephadex G-200柱层析并与标准分子量对比,DPSCG1和DPSCG2的分子量分别为1.22×10⁵D和2.79×10⁴D。